Brain MRI would show things like an acoustic neuroma in the ear. This is really used to rule out other things in the brain and such. Their is no such thing as an MRI of the inner Ear. The tests they have show how your vestibular system functions and show certain aspects of the inner ear. Unfortunately this is all the testing they have which is why a lot of us still struggle and have ups and downs.
I had the MRI and then after that I saw the specialist and he said that it does not show enough detail, unless it of the inner ear specifically. He then sent me for a Cat scan of the brain, inner ear, cochlea, sinus and orbits, I think. That was the most detailed, according to him. He is a specialist at a Vestibular center here in San Diego. Good luck.